package com.dzj.springcloud.lb;/*
 * @date:2021/8/9 14:24
 * @author: dzj
 **/


import org.springframework.cloud.client.ServiceInstance;
import org.springframework.stereotype.Component;

import java.lang.annotation.Annotation;
import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

@Component
public class MyLB implements LoadBalancer{

    private AtomicInteger atomicInteger=new AtomicInteger(0);

    //自旋锁
    public final int getAndIncrement(){
        int current;
        int next;
        do {
            current=this.atomicInteger.get();
            next=current>= 2147483647 ? 0 : current+1;

        }while (!this.atomicInteger.compareAndSet(current,next));
    System.out.println("=====next次数:"+next);
    return next;
    }
    @Override
    public ServiceInstance instances(List<ServiceInstance> serviceInstances) {
        int index=getAndIncrement() % serviceInstances.size();

        return serviceInstances.get(index);
    }
}
